Abstract
Pointing tasks form a significant part of human-computer interaction in graphical user interfaces. Fitts’ law (Fitts, 1954) and its variations (Mackenzie, 2003) are widely used to model pointing as a sequence of rapid aiming movements, especially for able-bodied users. Fitts’ Law predicts the movement time as a function of the width and distance to the target. This law is found to be very robust and works in many different situations (even in space and under water). However the application of Fitts’ Law for people with motor impairment is less clear. We have investigated also how the pointing performance of people with motor impairment varies from their able-bodied counterparts. In particular, we have studied how physical strength affects the pointing performance of people with and without motor impairment for different input devices. We have used this study to develop a simulator to help with the design and evaluation of assistive interfaces (Biswas and Robinson, 2008b). The simulator embodies both the internal state of a computer application and also the perceptual, cognitive and motor processes of its user. It takes a task definition and locations of different objects in an interface as input. It then predicts possible eye movements and cursor paths on the screen and uses these to predict task completion times. We hope this study will be helpful to understand and analyse the interaction patterns of people with motor impairment and design better assistive interfaces for them. It will also help in explaining motor action and developing better motor-behaviour models for motor impaired users.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Biswas P, Robinson P (2008a) A new screen scanning system based on clustering screen objects. Journal of Assistive Technologies, 2(3): 24–31
Biswas P, Robinson P (2008b) Automatic evaluation of assistive interfaces. In: Proceedings of International Conference on Intelligent User Interfaces (IUI’08), Canary Islands, Spain
Fitts PM (1954) The information capacity of the human motor system in controlling the amplitude of movement. Journal of Experimental Psychology, 47: 381–391
Flowers KA (1976) Visual ‘closed-loop’ and ‘open-loop’ characteristics of voluntary movement in patients with parkinsonism and intention tremor. Brain, 99: 269–310
ISO (2000) Ergonomic requirements for office work with visual display terminals (VDTs): requirements for non-keyboard input devices. ISO 9241-9:2000. International Organization for Standardization, Geneva, Switzerland
Kaplan RJ (2006) Physical medicine and rehabilitation review, 2nd edn. MacGraw Hill
Mackenzie IS (2003) Motor behaviour models for human-computer interaction. In: Carroll JM (ed.) HCI models, theories, and frameworks: toward a multidisciplinary science. Morgan Kaufmann, San Francisco, CA, US
Mathiowetz V, Weber K, Volland G, Kashman N (1984) Reliability and validity of hand strength evaluation. Journal of Hand Surgery, 9: 18–26
Rosenbaum DA (1991) Human motor control. Academic Press Inc., US
Smits-Engelsman BCM, Rameckers EAA, Duysens J (2007) Children with congential spastic hemiplegia obey Fitts’ Law in a visually guided tapping task. Journal of Experimental Brain Research, 177(4): 431–439
The Super-Switch (2007) Available at: http://rjcooper.com/super-switch/index.html (Accessed on 19 November 2009)
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2010 Springer-Verlag London Limited
About this paper
Cite this paper
Biswas, P., Robinson, P. (2010). The Effects of Hand Strength on Pointing Performance. In: Langdon, P., Clarkson, P., Robinson, P. (eds) Designing Inclusive Interactions. Springer, London. https://doi.org/10.1007/978-1-84996-166-0_1
Download citation
DOI: https://doi.org/10.1007/978-1-84996-166-0_1
Publisher Name: Springer, London
Print ISBN: 978-1-84996-165-3
Online ISBN: 978-1-84996-166-0
eBook Packages: EngineeringEngineering (R0)